锥形束CT在牙内陷诊断中的应用

The Role of CBCT in the Diagnosis of Dens Invaginatus

目的:探讨牙内陷的锥形束CT影像特征。方法:收集同济大学附属口腔医院就诊的40例患者其49枚牙内陷患牙的锥形束CT影像资料,对其影像特征进行分析归纳。结果:40例患者中共发现49枚牙内陷患牙,按Oehlers分型其中Ⅰ型35枚、Ⅱ型13枚、Ⅲ型1枚;发生于上颌侧切牙46枚,上颌切牙2枚,上颌尖牙1枚。49枚患牙的内陷畸形均发生于所涉及患牙的舌侧;47枚牙有1个凹陷,2枚牙有两个凹陷;3例患牙并发根尖周炎。CBCT图像显示:患牙在内陷层面,Oehlers分型为Ⅰ型的35枚和Ⅱ型13枚,在矢状面、冠状面均可见盲管征;OehlersⅢ型见双轨征;上述3型在横断面均见圆环征;大部分凹陷壁的密度与牙釉质的密度一致。结论:锥形束CT能准确诊断牙内陷,并为指导临床治疗提供可靠的影像学依据。

Objective:To assess the use of cone-beam computed tomography(CBCT)in the diagnosis of dens invaginatus.Methods:Randomly selected 49 sets of CBCT images(40 patients)with dens invaginatus,whose data were retrospectively reviewed.Results:Totally,49 dens invaginatus were found in 40 patients,including 35 teeth of OehlersⅠ,13 teeth of OehlersⅡ,1 teeth of OehlersⅢ.There were 46 maxillary lateral incisors,2 maxillary incisors and 1 maxillary canine.All occurred in the lingual side.47 dens invaginatus had one invagination,2 had two invaginations.3 cases suffered with periapical periodontitis.CBCT image:the blind tube sign was found in sagittal and coronal plane in 13 teeth of OehlersⅠand 35 teeth of OehlersⅡ,double track sign was found in OehlersⅢ.Ring sign was seen in transverse plane.The density of the wall of most invaginatus was consistent with the enamel.Conclusion:The use of CBCT was very useful for dens invaginatus diagnosis.It accurately revealed the morphology and relationship between the disease and surrounding tissues.